An elevator car is usually moved in an elevator shaft between two end positions, namely a first, upper end position in the region of a shaft ceiling and a second, lower end position in the region of a shaft base. The regions below or above an elevator car are normally accessible to service personnel for maintenance work. In order to avoid accidents involving crushing, protective spaces of sufficient size, in which service personnel can safely stand at all times, have to be provided between the car floor and the shaft ceiling and between car floor and shaft base.
The arranging of such a protective space below the elevator car requires, for example, provision of a relatively deep shaft pit. This is contradictory to utilization of a given building volume as efficiently as possible. In the design of an elevator it is a question of realizing such a shaft pit in space-saving manner. This problem was taken into account in patent specification WO 01/89977 A1.
WO 01/89977 A1 shows an elevator with an elevator car having a maintenance opening in the region of the car floor. Accordingly, the shaft pit is accessible by way of the maintenance opening for maintenance work. Since the maintenance opening remains open during the presence of service personnel in the shaft pit the protective space now extends from the shaft floor to the underside of the car roof. Consequently, an additional protective space does not have to be provided below the elevator car and the shaft pit depth can be designed to be minimal.
In an elevator car with a maintenance opening in the car floor region it is necessary to take into account special precautionary measures, since the maintenance opening may be opened only if it is possible to safely walk on the shaft base. This is guaranteed solely in the lower, end position of the elevator car. If the maintenance opening is opened in an upper position of the elevator car in the shaft a fall from the elevator car onto the shaft base is connected with substantial risk of injury.